SEM comparison between dentin surfaces etched with acid agents and dentin surfaces irradiated with laser

Abstract

Preliminary research has indicated that laser etching may create a roughened dentin surface similar to that produced by enamel acid etching. Localized melting and recrystallization produce fungiform projections on dentinal surfaces. Consequently, this surface may present potential for bonding composite resin restorations. The purpose of this investigation was to compare using SEM and dentin topography that results from both acid etching and laser treatment, and also make comparisons between the effectiveness of various laser exposure parameters. In addition, a shear bond strength pilot study was done to corroborate the SEM results.Forty-two molars were collected and randomly divided into six groups. Dentin surfaces were prepared by horizontal section through the middle third of the teeth crown and finished with 600-grit paper. Five of the groups were laser treated with LX-20 CO2 surgical laser. The dentin treatments of each group were as follows: Group #1: Dentin etched with 10% Maleic Acid, Group #2: Dentin irradiated with CO2 laser at 2W mode 5, Group #3: Dentin etched with 10% Maleic acid and 3W mode 5 and then etched with 10% Maleic acid, Group #5: Dentin irradiated at 3W mode 7, Group #6: Dentin irradiated at 3W mode 9.